Abstract P521: Association Between Dietary Phytosterols and Risk of Cardiovascular Disease Mortality in US Adults: Findings From the Third National Health and Nutrition Examination Survey (NHANES III), 1988-1994

Introduction: Phytosterols (plant sterols) are naturally occurring components of plant food sources, including vegetable oils, nuts, cereals and legumes. Their chemical structure impedes intestinal cholesterol absorption and regular consumption has been related to lower serum low-density cholesterol (LDL-C), a causal risk factor for cardiovascular disease (CVD). The association between dietary plant sterol intake and CVD has yet to be determined. Objective: We aimed to examine the association of phytosterol consumption in the diet with cardiovascular mortality in US adults the National Health & Nutrition Examination Survey III (NHANES III), 1988-1994. Methods: We conducted a prospective cohort analysis on National Health and Nutrition Examination Survey (NHANES, 1988-1994 [III]), linked with the National Death Index mortality data (2015) to associate dietary phytosterol intake from 24h dietary recall data with CVD mortality. We included 13,004 adults aged ≥20 years who were non-pregnant, free of CVD at baseline and completed ≥1 24h dietary recall with plausible caloric intake data. We excluded individuals with death occurring within 1 year of baseline. We created a database quantifying the phytosterol content of foods in the 24h dietary recall data and estimated usual intake by quintiles using the NCI method. We determined the risk function by regression calibration and estimated CVD mortality risk between the 10 th (Q1) and 90 th (Q5) percentiles of usual intake. Data was adjusted for sex, age, smoking status and ethnicity. Results: Over a mean±SD follow-up period of 21.2±5.1y, 949 CVD deaths occurred in a population with a mean±SD age of 44.2±14.3y, BMI 26.7±4.7 kg/m 2 and mean dietary plant sterol usual intake of 272.3 mg/day. The top sources of dietary phytosterols were from potatoes 23%), wheat and other grains (21%) and beans, legumes and nuts (13%). Mean usual intake plant intake in the 10 th (Q1) and 90 th (Q5) percentiles of the population was 150.1 and 414.0 mg/day. The estimated relative risk for CVD mortality between Q1 (ref) and Q5 was 0.972 (p<0.05). Conclusions: Preliminary analyses suggest a CVD death risk reduction of 2.8% in the highest versus lowest intakes of dietary plant sterols in the US population. We plan to expand the multivariable model to include the Healthy Eating Index (diet quality) and assess stratification by healthful and unhealthful sources of phytosterols and linear and non-linear dose response analyses to determine the robustness of the association. OSF Registration: osf.io/da4sg Funding: Amgen Scholars Program, Canadian Institutes of Health Research (CIHR), Banting and Best Diabetes Centre (BBDC), Toronto 3D Knowledge Synthesis and Clinical Trials foundation